JP3866611B2 - Recording stop processing method and data recording apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a recording stop processing method for recording stream data transferred by DMA (Direct Memory Access). The present invention also relates to a data recording apparatus for recording stream data transferred by DMA.
[0002]
[Prior art]
A recording device that records stream data such as video temporarily stores the stream data in a buffer, DMA-transfers the stored stream data, and records the stream data on a hard disk or an optical disk.
[0003]
[Problems to be solved by the invention]
Even if recording stop is instructed during recording of stream data, there is a problem that if the DMA transfer does not end normally, the recording cannot be stopped immediately.
[0004]
An object of the present invention is to provide a recording stop processing method and a data recording apparatus which are made in view of the above-described circumstances and can immediately stop a recording operation accompanied by a DMA transfer. is there.
[0005]
[Means for Solving the Problems]
In order to solve the above problems and achieve the object, a recording stop processing method and a data recording apparatus of the present invention are configured as follows.
[0006]
(1) According to the recording stop processing method of the present invention, stream data provided in response to a recording instruction is stored in a predetermined storage destination, the stored stream data is DMA-transferred in a unit of a predetermined data amount, and DMA When the stream data to be transferred is recorded in a predetermined recording destination, a recording stop instruction is input, and when the stream data stored in the storage destination is less than a predetermined data amount, the stream data is stored in the storage destination. Dummy data is added to the stream data, stream data with dummy data that has reached a predetermined data amount is DMA-transferred, DMA transfer is terminated, and recording of the stream data is stopped.
[0007]
(2) A data recording apparatus according to the present invention includes a storage means for storing stream data provided in response to a recording instruction, and a transfer for DMA transfer of the stream data stored in the storage means in a unit of a predetermined data amount Means for recording stream data DMA-transferred by the transfer means, and stream data stored in the storage means when a recording stop instruction is input when stream data is recorded by the recording means When the data amount is less than the predetermined data amount, dummy data is added to the stream data stored in the storage means, the stream data with dummy data reaching the predetermined data amount is DMA-transferred, and the DMA transfer is terminated. Control means for stopping the recording of the stream data.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
[0009]
A digital recording / playback apparatus (DVD-RTR recorder) according to an embodiment of the present invention will be described below with reference to the drawings.
[0010]
FIG. 1 is a block diagram for explaining the overall configuration of a digital recording / playback apparatus (DVD video recorder) with a hard disk drive HDD according to an embodiment of the present invention. This apparatus basically performs a real-time video recording using a recordable optical disk (DVD-RAM disk, DVD-RW disk, DVD-R disk, etc.) 100 and / or a hard disk. It also has a playback function for DVD-ROM discs and recorded DVD-R discs. In addition, using a high-speed access performance of the HDD and DVD-RAM drive, a playback function during recording such as time slip viewing is also provided.
[0011]
1 includes an encoder unit 601, a decoder unit 602, a main MPU (microcomputer; or central processing unit CPU) unit 604, a V (video) mixing unit 605, a frame memory unit 606, a key input unit 607, and a display unit 608. DVD-RAM (and / or DVD-R / DVD-RW) drive unit 609, D-PRO (data processor) unit 610, A / V input 612, TV tuner unit (BS / terrestrial analog tuner) 613, audio Digital I / F 631, audio D / A section 632, speaker 633 (illustration of the driving audio amplifier is omitted), video digital I / F 634, TV D / A section 636, external monitor TV 637, STC (system) Time counter) unit 650, HDD unit (for example, 0GB~100GB about HDD recorder units and / or large capacity of the IC memory) 700 is constituted by a selector unit 750, etc. of the audio signal.
[0012]
The D-PRO unit 610 includes a first-in first-out type FIFO unit (FIFO buffer) 610a or is externally attached. The FIFO buffer constituting the FIFO unit 610a includes a recording side FIFO and a reproducing side FIFO. The input / output control of the recording side / reproduction side FIFO and the remaining amount monitoring thereof are performed by a control program called a FIFO control unit 6045 written in the program ROM in the main MPU 604.
[0013]
Here, the recording-side FIFO and the reproduction-side FIFO are, for example, one FIFO buffer divided according to the ratio between the recording data and the reproduction data, and even if the capacity of the entire FIFO buffer is constant, the recording-side FIFO and the reproduction-side FIFO The capacity of each FIFO can be variable. For example, when the capacity of the FIFO buffer is 4 MB and the recording rate is three times the reproduction rate, a buffer capacity of 3 MB can be allocated to the recording side FIFO, and a buffer capacity of 1 MB can be allocated to the reproduction side FIFO. In addition, when the rate changes during recording / reproduction, for example, when the recording rate becomes 1/3 of the reproduction rate, the buffer capacity of the recording side FIFO may be reduced to 1 MB and the buffer capacity of the reproduction side FIFO may be increased to 3 MB. it can. As described above, there are the following methods for changing the distribution ratio on the recording side / reproducing side of the FIFO buffer in accordance with the rate. That is, by setting an address pointer at the boundary between the recording FIFO and the reproduction FIFO and changing the address pointer position according to the recording / reproduction rate, the proportion of the FIFO buffer on the recording / reproduction side can be changed. .
[0014]
When the capacity of the FIFO buffer is sufficiently large (for example, 16 MB), a method of fixing the capacity of each of the recording-side FIFO and the reproduction-side FIFO (for example, every 8 MB) can be considered.
[0015]
Read control from the disk drive unit 609 (or HDD unit 700) is performed by a control program called a read drive control unit 6046 written in the program ROM in the main MPU 604. Further, writing control to the disk drive unit 609 (or the HDD unit 700) is performed by a control program called a write drive control unit 6047 written in a program ROM in the main MPU 604.
[0016]
The main MPU unit 604 includes a ROM unit including the above control program (firmware) and other control parameters, and a work RAM unit 604a used when executing each program. The work RAM unit 604a includes a memory area called a VMG holding unit (not shown) that temporarily stores the management information (RTR_VMG) in FIG.
[0017]
The encoder unit 601 includes an A / D unit 614, a video encoding unit 616, an audio encoding unit 617 including a dual mono header setting unit 617a, an SP (sub-picture) encoding unit 618, a formatter unit 619, and a buffer memory unit 620. ing. In addition, the decoder unit 602 includes a separation unit 625 incorporating a memory 626, a video decoding unit 628 incorporating a reduced image (thumbnail) generation unit 628a, an SP (sub-picture) decoding unit 627, an audio decoding unit 630, a V-PRO ( The video processor) unit 638 is configured.
[0018]
Recording (recording of AV information) is performed via an encoder unit 601, a disc drive unit (DVD-RAM drive unit) using a replaceable (removable) DVD-RAM (or DVD-R / DVD-RW) disc 100. 609. The disc drive unit 609 can reproduce not only from the DVD-RAM (or DVD-R / DVD-RW) disc 100 but also from the DVD video (or DVD-ROM) disc 100. That is, DVD playback of the DVD family is performed via the decoder unit 602 via the disk drive unit 609 and the D-PRO unit 610. The function at the time of DVD video reproduction may be basically the same as that of a commercially available DVD video player.
[0019]
The actual video signal flow in the apparatus of FIG. 1 is as follows. First, for example, an AV (audio / visual) signal obtained from the TV tuner unit 613 is input to the A / D unit 614 and converted into a digital signal. Next, the converted digital signal is input to the video encoding unit 616, and the digital audio signal is input to the audio encoding unit 617. (In addition, when character data such as character broadcast is output from the TV tuner unit 613 in reception / recording of terrestrial analog broadcast, it is input to an SP (sub-picture) encoding unit 618. Reception / recording of terrestrial analog broadcast In recording, the video signal is digitized by the A / D unit 614, and then the input video signal is MPEG-compressed by the video (main video) encoding unit 616. The audio (sound) encoding unit 617 inputs the video signal. The audio signal is compressed by, for example, MPEG audio, and the input character data is run-length compressed by the SP encoding unit 618.)
In each of the encoder units 616 to 618, when packed, the data is packetized so as to have, for example, 2048 bytes, and the packetized signals (video data, audio data, and sub-picture data) are sent to the formatter unit 619. Entered. The formatter unit 619 packs and multiplexes the input packet data using the buffer memory unit 620 as appropriate, and outputs the multiplexed signals (video pack, audio pack, and sub-picture pack) to the D-PRO unit 610. Send to.
[0020]
The D-PRO unit 610 forms an ECC block every 16 packs / 16 sectors in the current DVD video (32 packs / 32 sectors or more in the next-generation DVD video), and adds error correction data thereto. The data stream thus obtained is recorded on the optical disc (DVD-RAM, DVD-RW or DVD-R) 100 by the disc drive unit 609 or recorded on the HDD unit 700. Here, when the disk drive unit 609 is busy due to seeking or track jumping, the recording data is temporarily stored in the HDD unit 700 (and / or a semiconductor memory not shown) as a temporary storage unit. It can be configured to store and wait until the disk drive unit 609 is ready for recording.
[0021]
Further, the formatter unit 619 creates segmentation information during recording (by GOP head interrupt or the like), and sends the created segmentation information to the MPU unit 604 periodically. The segmentation information includes the number of packs of VOBU (video object unit) that is a data access unit, the end address of the I picture from the beginning of the VOBU, the playback time of the VOBU, and the like. Each VOBU may include the video pack, audio pack, and / or sub-picture pack. The disk drive unit 609 can access the recording information of the disk 100 in units of this VOBU. In DVD-RTR (real-time recording / playback DVD), one video file is stored on one disc.
[0022]
Next, various operations of the apparatus of FIG. 1 will be described with reference to a flowchart. FIG. 2 is a flowchart for explaining the overall operation of the apparatus of FIG. Each process of this flowchart is controlled by the main MPU unit 604 of FIG. The main MPU unit 604 executes predetermined initial setting (step ST10) after the apparatus is activated. Thereafter, it waits for a key input from the user (key input from a remote controller (not shown) or an operation command from a reserved recording program). When there is a key input (step ST20), the input key is interpreted (TV reception channel switching command, recording start command, playback start command, etc.) (step ST30).
[0023]
For example, if the input key is interpreted as “recording start command” in the recording, the recording process to the recordable optical disk (DVD-RAM disk or the like) 100 and / or the HDD unit 700 loaded in the disk drive unit 609 is performed. Performed (step ST50).
[0024]
For example, if the input key is interpreted as a “reproduction start command” during reproduction, an optical disc (DVD-RAM disc, DVD-RW disc, DVD-R disc, or DVD video disc) loaded in the disc drive unit 609 is used. Playback processing from 100 is performed (step ST60).
[0025]
In the process of FIG. 2, when the recording process for the disk 100 (or HDD unit 700) and the reproduction process for the disk 100 (or HDD unit 700) overlap, the control unit (604) determines that the disk 100 (or HDD unit 700). Is prioritized (ST50 is prioritized over ST60 in FIG. 2).
[0026]
FIG. 3 is a flowchart for explaining interrupt processing in the apparatus of FIG. When entering the interrupt processing, since there are various factors in the interrupt, the interrupt factor is checked first (step ST70). If the interrupt factor is, for example, “interrupt processing when transfer to the D-PRO unit 610 for one pack is completed”, interrupt processing Recpack ++ (step ST72) for counting up the number of recording packs is executed. If the interrupt factor is, for example, “interrupt processing at the time of capturing segmentation information from the formatter unit 619”, an interrupt flag for capturing segmentation information 1 is set (step ST74). Although not shown, interrupt flag setting for capturing the segmentation information x (x = 1, 2, 3,...) Is also performed as appropriate. As described above, after the interrupt processing for each interrupt factor is performed, the flow returns to the other processing flow.
[0027]
FIG. 4 is a flowchart for explaining recording processing (recording of an MPEG program stream PS) in the apparatus of FIG. The main MPU unit 604 reads each file system data from the disk 100 (or HDD unit 700) loaded in the disk drive unit 609 (step ST500). The used capacity is calculated from the read data, and it is checked whether or not the disk 100 (or HDD unit 700) has a free capacity. When there is no free space, a warning message such as “no recording space” is displayed on the display unit 608 or the TV 637, and the process is terminated. When there is free space, a management file (VMG file) is read from the disk 100 (or HDD unit 700), and when there is no management file, a new VMG file is created and expanded in the RAM unit 604a ( Step ST506).
[0028]
After such pre-recording processing (step ST506) is performed, the process proceeds to initial setting for recording (step ST508). In this initial setting for recording, the STC unit 650 is reset, a write start address and a write command are set to each drive unit (disk drive unit 609, HDD unit 700, etc.), and initial settings (cell CELL, video) of the formatter unit 619 are set. The object unit VOBU, the program PG, and the program chain PGC are set) and the like. Following the initial setting, a recording start setting is made (step ST510). In this recording start setting, a recording start command is set in the encoder unit 601, and the segmentation information (the segment set in step ST508) is registered as a video object VOB.
[0029]
After recording starts, when data for the recording start amount (for example, 1 ECC block or more) is stored in the FIFO unit 610a (Yes in step ST512), the write address and write length in the disk drive unit 609 (or HDD unit 700) are determined, A write command is issued to disk drive unit 609 (or HDD unit 700) (step ST514). When there is an interruption for capturing the segmentation information (Yes in step ST516), segmentation information is captured from the formatter unit 619 (step ST518).
[0030]
In other words, when the data of the program stream PS taken into the encoder unit 601 has accumulated in the FIFO buffer of the FIFO unit 610a in a certain amount (one or more ECC blocks or one continuous data area CDA). (Yes in step ST512), the data is recorded on the disc 100 (or the HDD unit 700). At this time, the recording data segmentation information is appropriately taken into the work RAM unit 604a (step ST518).
[0031]
If a write error to the disk 100 (or HDD unit 700) occurs during writing (recording) started by the write command issued in step ST514 (yes in step ST521), the address information being recorded is stored in the work RAM unit. Once stored in 604a (step ST523), the process proceeds to a FIFO & recording start amount control process (step ST525). The address information once stored in the work RAM unit 604a can be appropriately recorded in the volume & file management information area (see FIG. 8B) of the disk 100 after the recording is completed. If a write error has not occurred (NO in step ST521), the process in step ST523 is skipped and the process proceeds to a FIFO & recording start amount control process (step ST525).
[0032]
While the recording continues (NO in step ST527), the processes in steps ST512 to ST527 are repeated. When a recording end key is input and recording ends (YES in step ST527), a recording end process (not shown) is executed. In this recording end processing, the remaining segmentation information is fetched from the formatter unit 619 and initialized, and the settings of the program chain information PGCI (segmentation information, I picture information, etc.) can be written in the management information VMG. In other words, the remaining segmentation information can be captured in the work RAM unit 604a, and the management information VMG can be updated based on the captured segmentation information.
[0033]
FIG. 5 is a flowchart for explaining processing in the case of reproducing digitally recorded video information in the apparatus of FIG. Here, the description will be made assuming that video information is normally recorded on the disc 100 loaded in the disc drive unit 609 (the same applies to reproduction from the HDD unit 700).
[0034]
First, it is checked whether or not the current mode is a playback mode (step ST610). If the playback mode is not set (NO in step ST610), the processing in FIG. 5 ends. If the playback mode is selected (YES in step ST610), the MPEG video decoding unit 628, the sub-picture (SP) decoding unit 627, and the audio decoding unit 630 are initialized (step ST620).
[0035]
After the initial setting, for example, data to be reproduced is determined based on a reproduction time designated by the user, and an address at which reproduction is started is determined based on address information and segmentation information corresponding to the determined data (step ST630). ). When the playback start address is determined, cell playback processing (step ST640) is executed. While the reproduction is continuing (NO in step ST650), the cell to be reproduced next is determined (step ST660), and the cell reproduction process (step ST640) is executed.
[0036]
If cell playback is completed (YES in step ST650), an error check (step ST670) is performed. When an error occurs at the end of playback (YES in step ST670), a display such as “reading error has occurred” is displayed on display unit 608 and / or TV 637 (step ST680), and playback end processing (step ST690) is executed. Then, the process returns to another processing state (for example, the key input waiting state at step ST20 in FIG. 2). If there is no error (NO in step ST670), other playback end processing is executed (step ST692), and the playback processing in FIG. 5 ends.
[0037]
FIG. 6 is a flowchart for explaining the contents of the cell playback process (step ST640) in the process of FIG. FIG. 7 is a flowchart for explaining the continuation of the process of FIG. In step ST6400 and others in FIG. 6, “FP” indicates the head position, and LBN indicates the logical block number. For example, the start FP (LBN) of the reproduction cell indicates the start position of the cell from which reproduction is started indicated by a logical block number.
[0038]
First, based on the program chain information PGCI and time map information TMAPI included in the management information VMG, the start FP (LBN) and end FP (LBN) of the cell to be reproduced are determined, and the read FP is set as the cell start FP. "End address-start address" is set as the remaining cell length (step ST6400). The start address and read length of the data block (continuous data area CDA) to be read are set (step ST6402). If the read block length is shorter than the remaining cell length (Yes in step ST6404), “remaining cell length−read block length” is set as the remaining cell length (step ST6406). On the other hand, when the read block length is greater than or equal to the remaining cell length (NO in step ST6404), the read block length is set as the remaining cell length, and the remaining cell length is set to zero (step ST6408).
[0039]
Subsequently, a data read command is set in the disk drive unit 609 (step ST6410), and the start of read data transfer is awaited. If the transfer is started (YES in step ST6412), it waits for the read data to be stored in the FIFO buffer for 1 VOBU or more. When the data is stored in the FIFO buffer for 1 VOBU or more, data for 1 VOBU is read from this buffer, and the packs constituting this VOBU are examined.
[0040]
If the seamless connection flag (not shown) in the read VOBU data is set (YES in step ST6424), “read FP + read length” is set as the read FP, the MPEG decoder is set in the normal mode, and the system The clock reference SCR is read and set as appropriate, and the seamless connection flag is reset (step ST6426).
[0041]
When the transfer started in step ST6412 ends (YES in step ST6428), it is checked whether or not the next process is started. If it is started, the process proceeds to a FIFO & read block control process (step ST6445).
[0042]
After the FIFO & read block control process (step ST6445) is performed, if the remaining cell length becomes zero (YES in step ST6450), the process of FIGS. Return to ST650. If the remaining cell length is not zero (NO in step ST6450), the process returns to step ST6402, and the processes in FIGS. 6 to 7 are repeated.
[0043]
If the transfer started in step ST6412 has not ended (NO in step ST6428), there is a key input in step ST20 in FIG. 2 (YES in step ST6430 in FIG. 7), and the special playback mode is fast-forward FF (YES in step ST6432). ) The playback time and the recording time (current time) are compared (step ST6433). If the playback time and the recording time are different (NO in step ST6433), the jump direction for fast-forwarding is set as the positive direction, and the reading position read_fp is set according to the jump amount (step ST6434). When the playback time and the recording time match (Yes in step ST6433), step ST6433 is skipped.
[0044]
On the other hand, if the special playback mode is not fast-forward FF but fast-reverse FR (Yes in step ST6432, yes in step ST6436), the start time and the recording time (current time) are compared (step ST6437). If the start playback time and the recording time are different (NO in step ST6437), the jump direction for fast reverse is set to the negative direction, and the read position read_fp is set according to the jump amount (step ST6438). When the start time and the recording time match (Yes in step ST6437), step ST6438 is skipped.
[0045]
When the read position read_fp at the time of FF or FR operation is set in this way, the process of the read block (continuous data area DCA) at the time of special reproduction (FF or FR) is performed, and the process returns to step ST650 in FIG.
[0046]
In the processing of the read block, the read position read_fp can be determined based on the time map information TMAPI quoted in step ST6400 of FIG. 6 in consideration of the jump amount (see FIG. 8 for the contents of TMAPI). And will be described later).
[0047]
If there is no key input in the process of FIG. 7 (NO in step ST6430), the process returns to step ST6428 of FIG. If there is a key input and it is neither the FF key nor the FR key (NO in steps ST6432 and ST6436), the process proceeds to checking whether it is a recording start key (step ST6460).
[0048]
If the input key is a recording start key (during cell playback processing) (YES in step ST6460), the start address of the VOBU being played, the playback time, and the position of the VOBI (in the work RAM 604a in FIG. 1) are used as the recording start information ( The data is stored in the work RAM 604a (step ST6462), and the process returns to step ST6428 in FIG.
[0049]
If the input key is not a recording start key during playback processing (NO in step ST6460) and a recording end key (YES in step ST6464), the start address of the VOBU being played back, the playback time, and the position of VOBI (in the work RAM 604a in FIG. 1) ) Is stored in the work RAM 604a as the recording end information (step ST6462), and the process returns to step ST6428 of FIG.
[0050]
If the input key is not a recording start key during playback processing (NO in step ST6460), not a recording end key (NO in step ST6464), and is a playback key (YES in step ST6468), the pause state is canceled and the system time clock STC is released. Is started (step ST6470), and the process returns to step ST6428 of FIG.
[0051]
If the input key is not a recording start key during playback processing (NO in step ST6460), is not a recording end key (NO in step ST6464), and is not a playback key (NO in step ST6468), the process returns to step ST6428 of FIG.
[0052]
<Summary>
In the write control or read control for the FIFO buffer in the FIFO unit 610a shown in FIG. 1, the remaining FIFO amount is set so as to satisfy a predetermined “FIFO condition” in order to enable “playback while recording without interruption”. The following controls are performed while monitoring:
(1) During recording process: When the recording-side FIFO buffer remaining amount exceeds a predetermined value (for example, 75%), the write amount (write size) to the drive is increased (ECC block unit = 16 or 32 sector units). Increase), or increase the number of writes to the drive (per unit time), or increase the amount of data to be buffered in the recording FIFO (increase in ECC blocks);
Here, in order to prevent the FIFO from overflowing, the amount of writing to the drive is increased. In other words, the read amount from the FIFO is increased.
[0053]
(2) During reproduction processing: When the remaining amount of the reproduction-side FIFO buffer becomes a predetermined value (for example, 25%) or less, the read amount (read size) from the drive is increased (increased in units of ECC blocks), or Increase the number of reads (per unit time). In other words, the amount of writing to this FIFO is increased.
[0054]
(3) When the recording process and the reproduction process overlap, the recording process is given priority.
[0055]
As the predetermined “FIFO condition”, for example, the following two can be adopted:
A> The recording FIFO does not overflow;
B> The reproduction side FIFO is not emptied.
[0056]
The input / output rate for the FIFO buffer can have the following characteristics, for example:
a> The input rate of the recording side FIFO depends on the transfer rate (variable rate) from the MPEG encoder, and the output rate of the recording side FIFO depends on the transfer rate to the drive;
b> The input rate of the reproduction side FIFO depends on the transfer rate from the drive, and the output rate of the reproduction side FIFO depends on the transfer rate to the decoder.
[0057]
FIG. 8 is a diagram for explaining the contents of management information (RTR_VMG) recorded by the apparatus of FIG. Here, a case where the volume space information as shown in FIG. 8B is recorded in the information recording area of the DVD-RAM disk 100 of FIG. 8A will be described as an example (recording information on the HDD unit 700). The data structure may be the same).
[0058]
As shown in FIG. 8B, the volume space of the disk 100 includes a recording area for volume and file management information, and a data area for recording user data (AV information and the like). As shown in FIG. 8C, this data area can record management information RTR_VMG and user data contents (video object VOB constituting AV information, etc.). The management information RTR_VMG is stored as a file of the video manager VMG.
[0059]
As shown in FIG. 8D, the management information RTR_VMG includes RTR video manager information RTR_VMGI, a movie AV file information table M_AVFIT, a still picture AV file information table S_AVFIT, original program chain information ORG_PGCI, user-defined information, It includes a program chain information table UD_PGCIT, a text data manager TXTDT_MG, and manufacturer information MNFIT.
[0060]
The program chain information PGCI is a data structure that represents the entire reproduction of the program chain PGC, and PGC indicates a series of programs PG (program set). PG is a logical unit of recorded contents, and PG is recognized or defined by the user. The PG in the program set is composed of one or more original cells (the playback unit of the first recorded content), and the PG is defined only in ORG_PGCI. In other words, it can be said that ORG_PGCI is information describing the cell playback order of the first recorded content. UD_PGCIT is a table describing one or more PGCIs edited by the user after recording.
[0061]
As shown in FIG. 8E, M_AVFIT includes movie AV file information table information M_AVFITI, one or more movie VOB stream information M_VOB_STI # 1 to M_VOB_STI # n, and movie AV file information M_AVFI. As shown in FIG. 8F, M_AVFI includes movie AV file information general information M_AVFI_GI, one or more movie VOB information search pointers M_VOBI_SRP # 1 to #n, and a number of movie VOB information M_VOBI corresponding to the search pointers. # 1 to #n.
[0062]
Each M_VOBI # includes movie VOB general information M_VOBI_GI, seamless information SMLI, audio gap information AGAPI, and time map information TMAPI, as shown in FIG. 8 (g). This TMAPI is used when performing special playback (cell playback in an order unique to an individual user using a user-defined PGC) and time search.
[0063]
The TMAPI includes time map general information TMAP_GI, one or more time entries TM_ENT # 1 to #r, and one or more VOBU entries VOBU_ENT # 1 # q, as shown in FIG. 8 (h).
[0064]
As shown in FIG. 8 (i), each TM_ENT includes VOBU_ENTN indicating the number of the corresponding VOBU entry, TM_DIFF indicating the time difference between the playback start time of the VOBU specified by the time entry and the calculated playback time, And VOBU_ADR indicating the target VOBU address. When the time unit TMU is represented by 600 fields in NTSC (or when the time unit TMU is represented by 500 fields in PAL), the “calculated playback time” for the time entry #j is TMU × (j−1) + TM_OSF. The VOBU_ADR represents the target VOBU address by the total size of the preceding VOBUs of the VOB when the VOBU size is expressed in units of sectors.
[0065]
In the data configuration as exemplified above, in order to start reproduction from the middle of a certain VOBU, the access point must be determined. Let this access point be a time entry point. This time entry point is located at a position separated from the position indicated by the movie address information of VOBU by the time difference indicated by the time difference information TM_DIFF in the time entry TM_ENT. This time entry point becomes a special reproduction start point (or time search point) indicated by the time map information TMAPI.
[0066]
Each VOBU entry includes reference picture size information 1STREF_SZ, VOBU playback time information VOBU_PB_TM, and VOBU size information VOBU_SZ as shown in FIG. 8 (j). Here, VOBU_PB_TM represents the playback time of the corresponding VOBU in video field units. The reference picture size information 1STREF_SZ represents the size of the first reference picture (corresponding to the MPEG I picture) of the VOBU in units of sectors.
[0067]
Normally, the “VOBU time interval” is represented by the number of fields in the VOBU entry. As another method, the “clock interval from one VOBU to the next VOBU” can be used to represent the “VOBU time interval”. "Count value by" can also be used. As a specific example, “the difference value between the presentation time stamp PTS at the head position of one VOBU and the PTS value at the head position of the immediately following VOBU” represents the “VOBU time interval”. be able to. In other words, “the time interval in the unit can be indicated by the differential value of the clock counter in the specific unit”.
[0068]
Next, the D-PRO unit 610 of the digital recording / playback apparatus shown in FIG. 1 will be further described. The D-PRO unit 610 of the digital recording / playback apparatus includes the following (1) to (6).
[0069]
(1) Microprocessor interface (address / data bus)
(2) Buffer memory controller
(3) ATA / ATAPI host interface
(4) DMA controller (for ATA HDD and ATAPI DVD-RAM)
(5) MPEG2 AV encoder interface
(6) AV decoder interface
Further, the FIFO unit 610a of the D-PRO unit 610 has a channel 1 (recording area) and a channel 2 (playback area) as shown in FIG.
[0070]
The digital recording / reproducing apparatus performs A / D conversion on the video / audio input signal by the A / D unit 614 and encodes it by the encoder unit 601. The stream data in the DVD video recording format obtained by encoding is received via the MPEG2 AV encoder interface of the recorder data stream I / O control LSI (D-PRO unit 610), and is temporarily written in channel 1 of the FIFO unit 610a. I'm stuck. Subsequently, the stream data is read from the channel 1 and DMA-transferred on the ATA / ATAPI bus by the DMA controller in the D-PRO and recorded on the designated drive of either the HDD unit 700 or the disk drive unit 609. Is done.
[0071]
During reproduction, stream data is read from the designated HDD unit 700 or disk drive unit 609, and the read stream data is DMA-transferred on the ATA / ATAPI bus by the DMA controller of the D-PRO unit 610, and the FIFO The data is once written in the channel 2 of the section 610a. Subsequently, the stream data is read from the channel 2 and input to the decoder 602 via the AV decoder interface. Thereafter, the stream data is decoded by the decoder 602, D / A converted by the D / A converter 632, and output as a video / audio output signal.
[0072]
Here, each register of the D-PRO unit 610 will be described. Registers in the buffer memory controller that control input / output of a 64 Mbit SDRAM connected to the outside of the D-PRO unit 610, and registers in the DMA controller that perform data transfer with the ATA / ATAPI drive of the D-PRO unit 610 explain. Both registers are registers that can be written to or read from the main MPU unit 604.
[0073]
First, the registers inside the buffer memory controller will be described.
[0074]
RADP1 / RADP2 register (Read Address Pointer)
The RADP1 / RADP2 register is a register for designating a read pointer of the FIFO unit 610a allocated to the channel 1 and the channel 2 of the FIFO unit 610a. This is a register that can be written to or read from the main MPU unit 604.
[0075]
The RADP1 register is used for channel 1 read pointer setting, and the RADP2 register is used for channel 2 read pointer setting. When reading, the current address pointer is returned. Further, the address increases when stream data is read from the FIFO unit 610a to the AV decoder interface or the DMA transfer controller. When the address pointer reaches the final address of channel 1 and channel 2, it goes around the area in each channel and returns to the start address of each channel. RADP1 catches up with WADP1, but cannot overtake it. When RADP1 catches up with WADP1, channel 1 becomes empty. The relationship between RADP2 and WADP2 is the same.
[0076]
WADP1 / WADP2 register (Write Address Pointer)
The WADP1 / WADP2 registers are registers for setting write pointers assigned to the channels 1 and 2 of the FIFO unit 610a. This is a register that can be written to or read from the main MPU unit 604. The WADP1 register is used for channel 1 write pointer setting, and the WADP2 register is used for channel 2 write pointer setting. When reading, the current address pointer is returned. Further, the address increases when stream data is written from the MPEG2 AV encoder interface or the DMA transfer controller. When the address pointer reaches the final address of channel 1 and channel 2, it goes around the area in each channel and returns to the start address of each channel. WADP1 catches up with RADP1, but cannot overtake it. When WADP1 catches up with RADP1, channel 1 becomes full. The relationship between RADP2 and WADP2 is the same.
[0077]
Second, a register in the DMA controller that performs data transfer with the ATA / ATAPI drive of the D-PRO will be described. As in the digital recording / playback apparatus shown in FIG. 1, in the case of a two-drive configuration, there are two DMA controllers, one for ATA HDD and one for ATAPI DVD-RAM. In this case, there is one set of the following registers in each DMA controller.
[0078]
LENGTH register
The LENGTH register is a register for setting the length of one block to be transferred between the ATA HDD or the ATAPI DVD-RAM drive in units of words (2 bytes). For example, in the case of the DVD format, since one block (= 1 sector) is 2048 bytes, 0x400 (= 1024) is set. In the case of HDD, since one sector is 512 bytes, the same value 0x400 is set with one block being four sectors in order to match the DVD format.
[0079]
NBLOCK register
The NBLOCK register is a register for setting the total number of data blocks to be transferred to and from the ATA HDD or ATAPI DVD-RAM drive by one transfer command operation. For example, if 0x100 is set, 256 sectors can be transferred. When this register is read, it indicates the remaining number of transfer blocks. Decrement each time one block is transferred.
[0080]
DMACTL register
The first bit “DIR” of the LSB indicates the DMA transfer direction. When DIR = 1, ATA / ATAPI drive → D-PRO, and when DIR = 0, D-PRO → ATA / ATAPI drive.
[0081]
“START” of the first bit of the MSB is a register for starting one DMA transfer by writing one shot.
[0082]
When the main MPU unit 604 reads the NBLOCK register when the FIFO unit 610a becomes empty when recording is stopped, the number of remaining blocks of the last DMA transfer can be determined. Based on this value, the total number of sectors during recording is determined.
[0083]
Next, the recording stop process will be described with reference to FIGS.
[0084]
FIG. 10 is a flowchart for explaining the recording stop process. Note that the recording stop process is controlled by the main MPU unit 604.
[0085]
Stream data provided in response to a recording instruction input via the key input unit 607 is accumulated in the channel 1 of the FIFO unit 610a. The stream data accumulated in channel 1 of the FIFO unit 610a is DMA-transferred in units of a predetermined amount of data and recorded, for example, in the HDD unit 700 (ST101). In other words, DMA transfer is not possible when the predetermined data amount is not reached.
[0086]
During the above recording (NO in ST102), a recording stop instruction is input via the key input unit 607 (YES in ST103), and the stream data accumulated in the channel 1 of the FIFO unit 610a must reach the data amount of DMA transfer. If (YES in ST104), dummy data is added to the stream data stored in channel 1 of the FIFO unit 610a (ST105), and stream data with dummy data reaching a predetermined data amount is DMA-transferred (ST106). ). Thereby, the DMA transfer is completed (ST108), and as a result, the recording of the stream data is stopped.
[0087]
Here, the end of DMA transfer will be supplemented. As shown in FIG. 9, the FIFO unit 610a has a recording area (channel 1) and a reproduction area (channel 2), and the write status of stream data in the recording area is the first write address pointer (WADP1). It is managed by. Further, the read status of the stream data from the recording area is managed by the first read address pointer (RADP1). Also, the writing status of the stream data in the reproduction area is managed by the second write address pointer (WADP2). The state of reading stream data from the reproduction area is managed by the second read address pointer (RADP2). When the first read address pointer catches up with the first write address pointer and the recording area is detected empty, the first write address pointer is set outside the area, that is, at the end of the reproduction area, and the DMA transfer is performed. finish.
[0088]
FIG. 11 is a flowchart for explaining a recording stop process during time slip reproduction. Note that the recording stop process is controlled by the main MPU unit 604.
[0089]
Assume that recording and playback operations are performed in parallel as follows (ST201). That is, the stream data provided corresponding to the recording instruction input via the key input unit 607 is accumulated in the channel 1 of the FIFO unit 610a, and the stream data accumulated in the channel 1 of the FIFO unit 610a is a predetermined value. DMA transfer is performed in units of data amount and recorded in the HDD unit 700, for example. During this recording operation, stream data provided from the HDD unit 700 in response to a playback instruction input via the key input unit 607 is accumulated in the channel 2 of the FIFO unit 610a by DMA transfer, and the channel of the FIFO unit 610a 2 is reproduced and output. The program being recorded is played back in parallel with the recording and playback operations described above (time slip playback).
[0090]
During the recording and reproduction described above (NO in ST202), a recording stop instruction is input via the key input unit 607 (YES in ST203), and the stream data accumulated in the channel 1 of the FIFO unit 610a has reached the data amount of DMA transfer. If not (YES in ST204), dummy data is added to the stream data accumulated in channel 1 of the FIFO unit 610a (ST205), and stream data with dummy data reaching a predetermined data amount is DMA-transferred (ST205). ST206). Thereby, the DMA transfer is completed (ST208), and as a result, the recording of the stream data is stopped.
[0091]
Here, the end of DMA transfer will be supplemented. As shown in FIG. 9, the FIFO unit 610a has a recording area (channel 1) and a reproduction area (channel 2), and the write status of stream data in the recording area is the first write address pointer (WADP1). It is managed by. Further, the read status of the stream data from the recording area is managed by the first read address pointer (RADP1). Also, the writing status of the stream data in the reproduction area is managed by the second write address pointer (WADP2). The state of reading stream data from the reproduction area is managed by the second read address pointer (RADP2). When the first read address pointer catches up with the first write address pointer and the recording area is detected empty, the first write address pointer is set outside the area, that is, at the end of the reproduction area, and the DMA transfer is performed. finish.
[0092]
When the encoder unit 601 finishes outputting the stream data in response to the recording stop instruction, if the data accumulated in the FIFO unit 610a is insufficient, the DMA transfer cannot be completed. Therefore, dummy data corresponding to the shortage is added to the data stored in the FIFO unit 610a, and the DMA transfer is terminated. That is, it is not necessary to reset the DMA transfer, and high-speed recording stop processing is possible.
[0093]
Note that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention in the implementation stage. In addition, the embodiments may be appropriately combined as much as possible, and in that case, the combined effect can be obtained. Further, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent requirements are deleted from all the constituent requirements shown in the embodiment, the problem described in the column of the problem to be solved by the invention can be solved, and the effect described in the column of the effect of the invention Can be obtained as an invention.
[0094]
【The invention's effect】
According to the present invention, it is possible to provide a recording stop processing method and a data recording apparatus capable of immediately stopping a recording operation accompanied by DMA transfer.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating an overall configuration of a digital recording / playback apparatus with HDD (DVD video recorder) according to an embodiment of the present invention.
FIG. 2 is a flowchart for explaining the overall operation of the apparatus shown in FIG.
FIG. 3 is a flowchart for explaining interrupt processing in the apparatus of FIG. 1;
FIG. 4 is a flowchart for explaining recording processing in the apparatus of FIG. 1;
FIG. 5 is a flowchart for explaining playback processing in the apparatus of FIG. 1;
6 is a flowchart for explaining the contents (part 1) of the process during cell playback in the process of FIG. 5;
FIG. 7 is a flowchart for explaining the contents (part 2) of the process during cell playback in the process of FIG. 5;
8 is a view for explaining the contents of management information (RTR_VMG) recorded by the apparatus of FIG. 1. FIG.
FIG. 9 is a diagram illustrating a relationship between a recording area, a reproduction area, and pointers in a FIFO unit.
FIG. 10 is a flowchart for explaining recording stop processing;
FIG. 11 is a flowchart for explaining recording stop processing during time slip reproduction;
[Explanation of symbols]
100: Optical disc / information medium
601. Encoder unit
602: Decoder unit
604 ... Main MPU section
604a: Work RAM section
6045 ... FIFO control unit
6046 ... Read drive controller
6047 ... Write drive controller
609: Disk drive unit
610 ... D-PRO part
610a ... FIFO section
700 ... HDD section

Claims (6)

Stream data provided from the outside in response to the recording instruction is accumulated in a recording area of the recording area and the reproduction area where the boundary is delimited by an address pointer , and the accumulated stream data is stored in a predetermined amount of data. DMA transfer is performed in units, stream data transferred by DMA is recorded in a predetermined recording destination, and stream data provided from the recording destination is stored in the reproduction area by DMA transfer in response to a reproduction instruction. , When alternately executing the playback operation of playing back and outputting the accumulated stream data to the outside ,
According to the ratio between the recording rate and the reproduction rate, the boundary position between the recording area and the reproduction area by the address pointer is variably controlled,
When a recording stop instruction is input and the stream data accumulated in the recording area is less than a predetermined data amount, dummy data is added to the stream data accumulated in the recording area , and a predetermined data amount DMA transfer of the stream data with dummy data that has reached to end the DMA transfer and stop recording the stream data.
And a recording stop processing method.   The write status of stream data to the recording area is managed by a write address pointer, the read status of stream data from the recording area is managed by a read address pointer, and the read address pointer is the write address pointer. 2. The recording stop processing method according to claim 1, wherein when the recording area is detected as being empty, the write address pointer is set outside the recording area and the DMA transfer is terminated.   The status of writing stream data to the recording area is managed by a first write address pointer, and the status of reading stream data from the recording area is managed by a first read address pointer. The stream data write status to the area is managed by a second write address pointer, the stream data read status from the playback area is managed by a second read address pointer, and the first read address When the pointer catches up with the first write address pointer and the recording area is detected as empty, the first write address pointer is set at the end of the reproduction area and the DMA transfer is terminated. The recording stop processing method according to claim 1.   Storage means having a recording area and a reproducing area, the boundary of which is delimited by an address pointer;
  Recording means for storing stream data provided from outside in the recording area, and recording the stored stream data;
  Reproduction means for reading the stream data recorded in the recording means and storing it in the reproduction area, and reproducing the accumulated stream data;
  A storage capacity control means for variably controlling a boundary position between the recording area and the reproduction area by the address pointer according to a ratio between a recording rate and a reproduction rate;
  Transfer means for DMA transfer of stream data in units of a predetermined amount of data at the time of recording stream data by the recording means and at the time of reproducing stream data by the reproducing means;
  When the recording operation by the recording unit and the reproducing operation by the reproducing unit are performed in parallel, a recording stop instruction is input, and the stream data accumulated in the recording area does not reach a predetermined data amount , Dummy data is added to the stream data stored in the recording area, the stream data with dummy data that has reached a predetermined data amount is DMA-transferred, DMA transfer is terminated, and stream data recording is stopped. Control means to
  A data recording apparatus comprising:   The write status of stream data to the recording area is managed by a write address pointer, the read status of stream data from the recording area is managed by a read address pointer, and the read address pointer is the write address pointer. 5. The data recording apparatus according to claim 4, wherein when the recording area is detected as being empty, the write address pointer is set outside the recording area and the DMA transfer is terminated.   The status of writing stream data to the recording area is managed by a first write address pointer, and the status of reading stream data from the recording area is managed by a first read address pointer. The stream data write status to the area is managed by a second write address pointer, the stream data read status from the playback area is managed by a second read address pointer, and the first read address When the pointer catches up with the first write address pointer and the recording area is detected as empty, the first write address pointer is set at the end of the reproduction area and the DMA transfer is terminated. The data recording apparatus according to claim 4.

Images